Cryogenian magmatic activity and early life evolution

Abstract

Data from the Qinling Orogenic Belt in China indicate that a strong magmatic-volcanic event on the Snowball Earth during the Cryogenian age (approximately 720–635 million years ago) was followed by a dynamic period of accelerated evolution of early life through the Ediacaran period. The studied volcanics of the Cryogenian Yaolinghe group are mainly represented by andesite, dacite and rhyolite, with minor amounts of basalt, trachy andesite and trachyte towards the top, which formed in the environment of an active island arc related to a continental margin. Compared with average felsic volcanics, the studied Cryogenian marine volcanic strata are enriched (1.5–30.6 times) in Co, Cr, Bi, Ni, Se, Ga, As, Cu, Ba, V, and Zn. Elemental concentrations (P, Cd, Co, Ni, and Se) of the studied volcanics are more than 5–26.4 times those in the contemporaneous Liantuo tillite. We propose that Cryogenian magmatic and volcanic activity increased the flux of some trace nutritional elements into the oceans which possibly provided essential nutrients for the development of early life.

Paleontological Evidence for Dinoflagellates and Ciliates as Early Eukaryotes

“…The proposed timing of dinoflagellate divergence, around 650 Ma, corresponds approximately with the Cryogenian-Ediacaran boundary. This marked a transition from a period including the most extensive glaciations ever recorded on Earth to warmer oceans and greatly accelerated evolution of early life [60]. The earliest acritarchs are large unornamented leiospheres and acanthomorphs that preceded the Cryogenian glaciations.…”

Petrogenesis and Rb-Sr Isotopic Characteristics of Paleo-Mesoproterozoic Mirgarani Granite Sonbhadra Uttar Pradesh India: Geodynamics Implication for Supercontinent Cycle

“…The Cryogenian Period ca. 720-635 Ma, which occurred about 700 Ma may have been a result of the breakup of Rodinia that began about 725 Ma [111] , and the subsequent amalgamation of Gondwanaland. c. 620-580 Ma Gondwanaland/Pannotia [112,113] ; the break out of Laurentia from Rodinia at 725 Ma marks the re-organization of lithospheric plate motion that resulted in the Pan-African-Brasiliano orogeny.…”